Screen.



- PATENTED MAR. 22,1904. T. L. & T.J. STURTBVANT.

SCREEN.

APPLICATION FILED AUG. 31, 1901.

H0 MODEL. 2 SHEETS-SHEET 1 Il/ 0 I I. I y) W 10 u a Jim/6mm.

0 1%omwslfltwrfi2na2fi, Wimeasea, Momms'eIAS'twJ-evwnt,

No. 755,073. PATEN-I'EDMAR. 22', 1-904. T. L. &-T.J. STURTEVANT.

SCREEN. nrmouxon nun we. 31, 1901.

' SHEETS-SHEET 2.

no MODEL.

eiiof No. 755,073. i Patented March 22, 1904.

- UNITED STATE PATENT ()FFIOE.

THOMAS LEGGETT STURTEVANT, or NEWTON, AND THOMAS J. STURTE- VANT, or QUINCY, MASSACHUSETTS, ASSIGNORS TO THE STURTEVANT MILL COMPANY, OF PORTLAND, MAINE, AND BOSTON, MAssAoHU- SETTS, A CORPORATION.

SCREEN.

SPECIFICATION forming part of Letters Patent N0. 755,073, dated March 22, 1904.

V I 'Applioation filed August 31, 1901I Serial No. 73,925. (No model.)

I all whom y 607M367: In said drawings, Figure 1 is a side view, Be it known that we, THOMAS LEGGETT partly in section, of the supporting-frame for STURTEVANT,I8SidiI1gatN6WtOI1,.lntl16COuDty the screen-box, the screen-box, and feedingof Norfolk, and THOMAS J. STURTEVANT, rehopper and the mechanism for imparting 5 siding at Quincy, in the county of Middlesex, movement to the said hopper. Fig. 2 is a State of Massachusetts, citizens of the United front view of the screen-box and its parts, States, have invented certain new and useful showing also a portion of the delivery-chutes Improvements in Screens, of which the folfor the screened material and the tailings, the lowing is a specification, reference being had shaking mechanism for the screen-box being o therein to the accompanying drawings. clearly shown in this view. Figs. 3 and 4 are The present invention relates to screens for detail views of the lower end of the screenseparating coarse and fine materials, the mabox. terials in connection'with which the apparatus Referring to the drawings by numerals, like is designed to be used being broken vitreous numbers indicating like parts in the several 15 material, although it willbe understood that views, 1 indicates a frame of any suitable conit may, if desired, be used for screening, any struction, the present frame being shown as other material, and has for its object to proconsisting of base-pieces and uprights, and vide a construction in which a maximum area at the upper end of said frame is a rigid supof screening-surface will be provided in comport formed of a block 2, which will be termed 2o pact arrangement, so that the screen while in the description hereinafter a poundingcapable of a large output is comparatively block. Asimilar pounding-block3is mountsmall, occupies but little space, is convenient ed on'the base of the frame, as clearly shown for shipping, and because of its compact conin Fig. 1; Resting upon the said pounding- 7o struction may be made much stronger and blocks 2 and 3 is the inclined screen-box 4,

25 more capable of resisting wear on its active said box being shown in the present instance parts than a screening-machine havingthe as supported by iron straps 5, secured to its same screening area would be if its screeningunder side, said straps 5 being provided at surfaces were less compactly arranged than in their upper and lower ends, respectively, with the present construction. In the present inbent-out portions 6,which restupon the pound- 3 vention an improved driving mechanism is ing-blocks 2 and 3 at the upper and lower ends, r

also provided which will impart the proper respectively, of the frame 1 and form supports i vibratory movements to the screening elefor the said inclined screen-box 4. The said ments, so as to thoroughly separate the matebox 4 is preferably held in position upon said 0 rial thereon, and yet not necessitate a rapid pounding-blocks by means of bolts 7, which 35 running of such driving parts, whereby wear .pass through holes in the said bent-out porand tear on the machine is eliminated, means tions 6, the said bolts 7 being long enough to for jarring the screens to cause movement of permit a limited vertical movement of the the material and sifting being also provided. screen-box for a purpose which will presently 5 Furthermore, an improved feeding device to appear, said bolts 7 having nuts 7* at their 4 deliver the material to be screened to the. upper ends. Secured to said screen-box 4 is screening-surfaces is provided which will ina depending lug 8 substantially midway the sure an even continuous feed to the screens, length of the box 4, and from said h1g8 deresulting in an evenspreading of the material pends one lever of a toggle, the said lever upon the screens, which facilitatesthe separabeing shown in the present case as made up 45 tion of the material under treatment. of two links 9, the said links 9 at their lower In the accompanying drawings is illustrated ends engaging with the end of an eccentricone embodiment of our invention. I rod or pitman 10, the other end of. said rod 10 being connected by an ordinary eccentricstrap with an eccentric 11, mounted on a shaft 12, which receives a rotary motion from any suitable power. (Notshown) The otherlever of the toggle is composed of two links 13, connected at their upper ends to the head of the said pitman 10, said links 13 being connected at their lower ends with a fixed part, said fixed part being shown in the present case as a lug 14 on the base of the screenframe. It will be seen that as the eccentric 11 is rotated a thrust will be imparted to the rod 10, which will force the toggle past the center and lift the screen-box until its upward movement is suddenly arrested by the nuts 7 of the bolts 7 and that after the said toggle has been thrown to the other side of the center the box 4 will drop upon the pounding-blocks 2 and 3, so that its downward movement will be suddenly arrested with sufficient force to jar and agitate the material upon the screens within the screen-box and cause it to slide down and sift through the screens. It will be seen, furthermore, that as the eccentric-rod 10 is drawn back during the revolution of the eccentric the toggle will be thrown to the other side of its center and the screenbox 4 will be again raised, so that to each revolution of the eccentric and reciprocation of the eccentric-rod 10 two shaking movements will be imparted to the said screen-box 4, so that a comparatively rapid vibration of the box 4 is secured. with a slow movement of the eccentric 11 and its rod 10.

It will be seen that the bolts 7, with their nuts 7, serve to limit the movement of the screen-box, and they also guide the said box so as to confine its movements to a vertical direction, and the material on the screen is agitated by the abrupt stopping of the vertical movements of the screen-box.

Attention is directed particularly to the fact that while the screen-box 4 and its screens are inclined to the vertical their movements are bodily in a vertical direction without changing the angle of inclination of the screenbox, and the material under treatment will because of this vertical shake or movement be thrown upward in a vertical line from the surface of the screen and will fall in the same vertical path and upon the same spot from which it was thrown by the shake, so that any movement of the material lengthwise the screen will be a sliding screening movement along the screen-surface and will not occur while the material is in the air. The result of this action is that the material is subjected to a thorough screening action and the entire area of the screen-surface is utilized, there being no tendency on the part of the material to be projectedlengthwise the screen and fall at a point forward of the point at which it is thrown from the screen by the shake, as would be the case if the shake or movement of the screen were in a direction 4 and running longitudinally thereof are a plurality of superposed screens 15, three being shown in'the present instance, and below each of said screens 15 is a screen-pan 16 to receive the fines or screened material. The lower end of the screen-box is provided with a series of guide-plates 17, which deflect the material sliding down the screens and screen-pans, said plates 17 being arranged in reverse posit-ion on each side of the box 4 alternately and being provided with inclined inner edges, so that during the operation of the'machine the tailings which fail to pass the screens will be deflected to one side of the screen-box and delivered to one of the delivery-chutes, as 18, while the fines or screened material will be diverted to the other side of the screen-box and into the other deliverychute, 19, the said deflecting plates being made, preferably,as shown in the detail views, Figs. 3 and 4, of solid triangular plates, which overlap slightly at their inner lower angles. and so form a very rigid construction and add materially to the strength of the, screen-box 4 and the screen-supports. The lower end of the said screen-box 4 is preferably provided with a perpendicularly-placed extension 20, (see ,Fig. 1,) which directs the material from the screens and screen-pans to the deliverychutes.

Mounted upon the upper end of the screenbox is a hopper-casing 21, the lower end of which is provided with a series of partitions 22, which divide the said hopper-casing into as many feedways as there are screens in the screen-box 4, with which the hopper-casing 21 is in communication, each of said feedways 23 leading to one of the screens in the screen-box 4. Said partitions 22 are provided at their upper ends with feed deflecting or regulating gates 24, which are adapted to be swung to various angular positions, as shown in Fig. 1, in which figure the said gates 24 are shown as pivoted to the tops of the said partitions 22 upon suitable pivot-rods 24, passing through the hopper-casing, any appropriate means for swinging said plates 24 on their pivots and maintaining them in their several adjusted positions being provided. It will be clear that by swinging the said pivoted plates to their various positions it is possible to so regulate the flow of material to the screens through the several feedways as that the flow may be accurately proportioned between the screens, a result which, in. connection wit t e novel feedways 23, if this should be desirable, and

thus put one or two of the screens in the screen box 4 out of service. Pivoted in said hoppercasing 21 above and clear of the plates 24 is a pendulum-like hopper or feeding-chute 25, which receives a regular swinging movement from a crank-arm 26, attached to the pivotrod of the hopper 25, said crank-arm being rocked by means of a pitman or crank rod 27, connected with a suitablecrank-wheel 28, said crank-wheel 28 being driven from any suitable power. (Not shown.) It will be seen that as the said swinging hopper 25 is given aregular movement during the rotation of the crankwheel 28 its lower feeding end will swing back and forth above the mouths of the several feedways 23,which lead to the screens, and it will be clear that the said hopper 25 will as it reverses motion for theIreturn swing make a slight dwell at the end of its stroke over the mouths of the two outer feedways 23,"so that if the entrances to said outer feedways were the same size as the entrance or mouth to the middle feedway a greater quantity of material would be deliveredto the said outer feedways and their screens than would be received by the said middle feedway and its screen. In order, therefore, to proportion the feed so that each screen shall receive the same amount of material, the feed-deflecting plates 24. are thrown to the proper position to proportion the size of the mouths of the outer feedways 23.to the time it takes'the hopper 25 to move twice over said feedways, making the mouths of the outer feedways smaller than that of the middle feedway, so that the delivery to the outer and inner feedways and their respective screens is made practically uniform. The

upper end of the said hopper-casing 21 carries a delivery-chute 29, which receives the material to be screened from any suitable spout 30 and delivers it to the swinging hopper 25.

While we have shown and described a particular structure, we do not wish to be understood as limiting our invention to any of the details of construction set forth, as what is shown and described is merely one embodiment of our invention, and it will be clear that the structure shown-may be widely varied within the range of mechanical skill without departing from the spirit of our invention, and we do not, therefore, limit our invention, except so far as-it is limited by the terms of the appended claims, to anything shown and described.

Having thus described our invention, what we claim, and desire to secure by Letters Patent of th United States, is

1. In a screen, the combination with a'suitable supporting-frame; of an inclined screenbox supported thereby; a toggle connected to said screen-box and to a fixed part; means for throwing said toggle past its center to impart an intermittent movement tosaid screen-box;

guides on said supporting-frame to confine the movements of the screen-box to a true vertical line and prevent lateral playthereof; and rigid stops to suddenly arrest the movements of the screen-box and cause a screening flow of the material; whereby skipping of the material over the screening-surface is avoided.

2. Ina screen, the combination with a suitable supporting-frame; of an inclined screenbox; rigid supports forming pounding-blocks upon which said screen-box normally rests; means for' securing said screen-box to said rigid supports, said means serving also to limit the vertical movements of said box and suddenly arrest such vertical movements; and

- a toggle for reciprocating said box and causing it to pound upon said rigid supports.

3; In a screen, the combination with a suitable supporting-frame; of an inclined screenbox; rigid supports forming pounding-blocks upon which said screen-box normally rests; securing-bolts to hold said box in position on said rigid supports and confine its movements to a vertical direction; adjustable stop-nuts on said bolts to limit the vertical movements of said screen-box; and a toggle for reciproeating said box and causing it to pound between said rigid supports and said limitingnuts.

45. In a screen, the combination with a suitable supporting-frame; of an inclined screenbox; supporting-straps secured to the under side of said screen-box; said straps having outwardly-bent portions to form supportingfeet for the said screen-box; rigid supports forming pounding-blocks upon which said feet rest; bolts passing through said outwardlybent straps to secure said screen-box to said rigid supports; said bolts allowing a limited vertical movement to said screen-box; and a toggle for reciprocating said screen-box and causing it to pound upon said rigid supports.

5. In a screen, the combination with a screen-box; of a plurality ofscreens therein; means for reciprocating said screen-box in a true vertical line .to prevent skipping of the material over the screen; an independent feedway for each of said screens, a feedinghopper movable over said feedways at right angles to the line of movement of said screenbox; and means for imparting a regular feeding movement to said hopper; so that it will deliver material to each of said screens in regular succession.

6. In a screen, the combination with a screen-box; of a plurality of superposed screens therein; independent feedways for said screens; means for reciprocating said screenbox in a true vertical line to prevent skipping of the material over the screens; ahopper pivoted above said feedways; means for swinging said pivoted hopper over said feedways at right angles to the line of movement of said screen-box, so that it will deliver material to each ofsaid screens in regular succession; and regulating-gates to control the mouths of said feedways and proportion the flow of material to the screens.

7 In a screen, the combination with an inclined screen-box; of a plurality of screens mounted therein; independent feedways for said screens; a hopper-box carried by said screen-box; a screen-feeding hopper in said hopper-box; means for moving said hopper over the mouths of said feedways with a regular feeding movement; and means for vertically reciprocating said screen-box.

8. In a screen, the combination with an inclined screen-box; of a plurality of screens mounted therein; independent feedways for said screens; a hopper-box carried by said screen-box; a screen-feeding hopper pivoted in said hopper-box above said feedways; means for imparting a regular swinging feeding movement to said hopper; and means for reciprocating said screen-box vertically.

9. In a screen and in combination; a vibrating screen-box; screens mounted therein; independent feed ways for said screens; a hopperbox carried by said vibrating screen-box; a delivery-chute entering said hopper-box; a screen-feeding hopper pivoted in said hopperbox intermediate said delivery-chute and said screen-feedways and means for swinging said hopper above said feedways so as to deliver material to each of said screens in turn.

10. The combination Witha plurality of vertically-reciprocating screens; of means for vibrating said screens; a series of independent horizontally-arranged feedways for said screens; a horizontally-swinging hopper in feeding relation to said screens; and means for giving a horizontal feeding swing to said hopper above the screen-feedways, so as to deliver material to each feedway at regular intervals.

11. In a screen, the combination with a single inclined screen-box; of means for vibrating said box; a plurality of superposed screens and screen-pans in said box; independent feedways for said screens; a pivoted feeding-hopper adapted to swing above said feedways and deliver material to each at regular intervals; and means for proportioning the flow through said feedways to the feeding intervals of the said hopper.

12. In a screen, the combination with an inclined screen-box of a plurality of superposed screens in said box; independent feedways for said screens; means for vibrating said screen-box; a hopper-casing mounted on said screen-box over said feedways; a pivoted hopper mounted in said casing above said feedways; means for imparting regular swing-' ing movements to said hopper, whereby it delivers to each feedway in turn; and a feedchute delivering to said swinging hopper.

13. In a screen, the combination with a supporting-frame, of an inclined screen-box mounted thereon, a plurality of superposed screens in said box, screen-pans beneath said screens, toggle mechanism for vibrating said box, independent feedways for said screens, a single swinging hopper to'deliver material to each of said feedways in turn, independent delivery-chutes for said screens and screen-pans, and inclined guide-plates for diverting the fines and tailings to opposite sides of the screenbox.

In testimony whereof we aflix our signatures in presence of two witnesses.

THOMAS LEGGETT STUR'IEVANT. THOMAS J. STUR'IEVANT. Witnesses:

P. B. MOURY, LLOYD MAKEPEACE. 

